Tuesday's recall involves 13,900 units, bringing the total number to 520,100 since the CPSC began issuing the warnings last year.

Safety officials say the risk is in the battery packs and have found a significant risk of overheating, smoke, fire and in some instances, explosions that cause burns and property damage, according to the CPSC.

Tuesday's recalls included two reports of property damage, including one recent incident in Louisiana resulting in approximately $40,000 of damage after the unit caught fire.